Heating apparatus with fan

ABSTRACT

A heating apparatus can have a sealed combustion chamber and a burner. The heating apparatus can have an air shutter that controls the amount of air that mixes with fuel directed toward the burner. The air shutter can be controlled by rotating a shaft that connects to the air shutter. The heating apparatus can also have a system of channels along its front face which direct air along the front face.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.13/678,346, filed Nov. 15, 2012, which is related to and claims priorityto Chinese Patent Application No. 201120452598.X, filed on Nov. 16,2011, and U.S. Provisional Application No. 61/562,846, filed on Nov. 22,2011, the entire contents of all of which are hereby incorporated byreference herein and made a part of this specification. U.S. ProvisionalApplication Nos. 61/368,637, filed Jul. 28, 2010, and 61/408,549, filedOct. 29, 2010, are also hereby incorporated by reference herein and madea part of this specification. U.S. Pat. No. 7,434,447, filed on May 30,2006, and U.S. patent application Ser. No. 12/797,511, filed on Jun. 9,2010, are also hereby incorporated by reference herein and made a partof this specification. Any and all applications for which a foreign ordomestic priority claim is identified in the Application Data Sheet asfiled with the present application are hereby incorporated by referenceunder 37 CFR 1.57.

BACKGROUND OF THE INVENTION

Field of the Invention

Certain embodiments disclosed herein relate generally to heatingdevices, and relate more specifically to fluid-fueled heating devices,such as, for example, gas heaters, fireplaces, stoves, and other heatingdevices.

Description of the Related Art

Many varieties of heaters, fireplaces, stoves, and other heating devicesutilize pressurized, combustible fluid fuels to generate a desired heatoutput. Some such devices operate with liquid propane gas, while othersoperate with natural gas. These heating devices achieve high internaltemperatures. However, such devices and certain components thereof havevarious limitations and disadvantages.

SUMMARY OF THE INVENTION

According to some embodiments, a heating apparatus can comprise a sealedcombustion chamber and a burner disposed within the sealed combustionchamber. The gas fireplace assembly can also comprise a fuel channel fordirecting fuel from a fuel source external the sealed combustion chamberto the burner, and an air shutter within the sealed combustion chamberthat comprises a rotatable sleeve configured to rotate about a shutteraxis and adjust the size of a shutter opening. The heating apparatus canalso comprise an air shutter control comprising a shaft, the air shuttercontrol mated with the air shutter such that rotating the shaft rotatesthe rotatable sleeve.

According to some embodiments, a heating apparatus can comprise a sealedcombustion chamber and a burner disposed within the combustion chamber.The combustion chamber can have a front face viewable to a user when thefireplace is in use. The heating apparatus can also comprise acombustion air inlet in fluid communication with the sealed combustionchamber to provide air to the burner and an exhaust air outlet in fluidcommunication with the sealed combustion chamber to remove exhaust airfrom the combustion chamber. An outer housing can surround at least aportion of the sealed combustion chamber. A system of channels cancomprise at least two of a top channel above the front face, a left sidechannel to the left of the front face, a right side channel to the rightof the front face, and a bottom channel below the front face. The atleast two channels can be configured to direct air to the front face ofthe sealed combustion chamber, and at least one fan can be positionedwithin the outer housing and configured to direct air into the system ofchannels.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to better understand the embodiments of the disclosure and tosee how it may be carried out in practice, some preferred embodimentsare next described, by way of non-limiting examples only, with referenceto the accompanying drawings, in which like reference characters denotecorresponding features consistently throughout similar embodiments inthe attached drawings.

FIG. 1 is a schematic view of a heating device.

FIG. 2 is a perspective view of an embodiment of a heating device.

FIG. 2A is a perspective view of an embodiment of a fuel delivery systemcompatible with the heating device of FIG. 2.

FIG. 3 is a perspective view of another embodiment of a heating device.

FIG. 3A is a partially disassembled perspective view of the heatingdevice of FIG. 3.

FIG. 3B is a perspective view of an embodiment of a fuel delivery systemcompatible with the heating device of FIG. 3.

FIGS. 4A-D show front, side, back and top views of an embodiment of anair shutter control.

FIG. 4E shows an exploded view of the air shutter control of FIGS. 4A-D.

FIG. 5 shows the air shutter control of FIGS. 4A-D attached to an airshutter.

FIG. 6 shows an embodiment of an air shutter control.

FIG. 7 is a perspective view of another embodiment of a heating device.

FIG. 8 is a partially disassembled cross-section side view of theheating device of FIG. 7.

FIG. 9 is a perspective view of a cooling structure.

FIG. 10 is a front view of the cooling structure of FIG. 9.

FIG. 11 is a cross-sectional side view of the cooling structure of FIG.9.

FIG. 12 is a perspective view of another embodiment of a heating device.

FIG. 13 is a partially disassembled cross-section perspective view ofthe heating device of FIG. 12.

FIG. 14 is a partially disassembled cross-section perspective view ofthe heating device of FIG. 12.

FIG. 15 is partially disassembled cross-section perspective view of theheating device of FIG. 12.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Many varieties of space heaters, wall heaters, stoves, fireplaces,fireplace inserts, gas logs, and other heat-producing devices employcombustible fluid fuels, such as liquid propane and natural gas. Theterm “fluid,” as used herein, is a broad term used in its ordinarysense, and includes materials or substances capable of fluid flow, suchas, for example, one or more gases, one or more liquids, or anycombination thereof. Fluid-fueled units, such as those listed above,generally are designed to operate with a single fluid fuel type at aspecific pressure or within a range of pressures. For example, somefluid-fueled heaters that are configured to be installed on a wall or afloor operate with natural gas at a pressure in a range from about 3inches of water column to about 6 inches of water column, while othersare configured to operate with liquid propane at a pressure in a rangefrom about 8 inches of water column to about 12 inches of water column.Similarly, some gas fireplaces and gas logs are configured to operatewith natural gas at a first pressure, while others are configured tooperate with liquid propane at a second pressure that is different fromthe first pressure. As used herein, the terms “first” and “second” areused for convenience, and do not connote a hierarchical relationshipamong the items so identified, unless otherwise indicated.

Direct vent fireplaces provide efficient heating and do not require achimney for operation. A direct vent fireplace can direct externalambient air through a combustion vent system for heat generatingcombustion, and thus does not deprive interior living spaces of oxygenor heated air. Direct vent fireplaces use a balanced flow of combustionair and exhaust gas moving through the combustion fluid intake andexhaust ducts to provide an aesthetically desirable flame in thefirebox. Desirable flame characteristics can include, for example,appearing similar to a natural wood-fire flame. The size, color andaction of the flames in the firebox can be adjusted by selectivelybalancing the flow of combustion air and exhaust gas. A balanced flowalso allows direct vent fireplaces to function in a thermally efficientmanner. Accordingly, an important part of the fireplace insert'sinstallation is to properly balance the combustion air intake flow andthe exhaust gas flow. A direct vent fireplace can also provide heat viaradiant energy transmitted through the glass enclosure of the fireplacefront face. In addition, the combustion chamber enclosure structurereaches elevated temperatures during fireplace operation, e.g. thefirebox, glass window, or the like. The combustion chamber of a directvent fireplace is desirably “sealed.” As will be appreciated by those ofskill in the art, as used herein a “sealed combustion chamber” is sealedto the extent that it effectively seals the space desired to be heated(usually an interior room) from (1) air from an external source (usuallyambient air from outdoors to be used in the combustion process and (2)exhaust created from the combustion process.

In addition, in some instances, the appearance of a flame produced bysome fluid-fueled units is important to the marketability of the units.For example, some gas fireplaces and gas fireplace inserts are desirableas either replacements for or additions to natural wood-burningfireplaces. Such replacement units can desirably exhibit enhancedefficiency, improved safety, and/or reduced mess. In many instances, aflame produced by such a gas unit desirably resembles that produced byburning wood, and thus preferably has a substantially yellow hue.

The amount of oxygen present in the fuel at a combustion site of a unit(e.g., at a burner) can affect the color of the flame produced by theunit. Accordingly, in some units, one or more components of the unit areadjusted to regulate the amount of air that is mixed with the fuel tocreate a proper air/fuel mixture at the burner. Such adjustments can beinfluenced by the pressure at which the fuel is dispensed.

The conventional insert-style fireplace insert is typically installedand balanced by first sliding the insert into a close-fit fireplacecavity so a limited access space is provided between the fireplaceinsert and the cavity's walls. The installer reaches through the limitedaccess space to connect the fireplace insert to the exhaust duct and theintake duct. The installer then balances the flow of combustion air andthe exhaust gas while the fire is burning in the firebox in order tovisually analyze the flame characteristics. Limited access to theadjustment mechanisms for the intake duct, the exhaust duct or an airshutter can make this balancing a time-consuming and labor intensiveprocess requiring multiple adjustments of the adjustment mechanismsduring installation.

Some fluid-fueled fireplace units generate hot surfaces about thevarious features of the fireplace. For example, fireplaces having asealed, or semi-sealed, or partially sealed window or viewing space onthe front face of the unit can reach unsafe temperatures due to the riskof burning the skin, or igniting other objects in close proximity to ortouching such a surface. In addition, thermal cycling experienced by theviewing space structure, or glass window, subjects the glass toincreased loads that can reduce the durability of the structure. Theproximity of the glass portion of a front face to the intense heatemitted by the fireplace burner increases these types of concerns andthe maintenance costs of the gas fireplace.

Certain embodiments disclosed herein reduce or eliminate one or more ofthe foregoing problems associated with existing fluid-fueled devicesand/or provide some or all of the desirable features detailed herein.Although certain embodiments discussed herein are described in thecontext of directly vented heating units, such as fireplaces andfireplace inserts, it should be understood that certain features,principles, and/or advantages described are applicable in a much widervariety of contexts, including, for example, vent-free heating units,gas logs, heaters, heating stoves, cooking stoves, barbecue grills,water heaters, and any flame-producing and/or heat-producingfluid-fueled unit or appliance, including without limitation units thatinclude a burner of any suitable variety.

Direct Vent Fireplace

For clarity and convenience, a direct vent fireplace without the coolingstructure discussed above will first be described with reference toFIGS. 1-5. It will be understood that one or more of the features of thefireplaces of FIGS. 1-2A and 3-5 could be used in other embodiments ofthe fireplaces discussed herein, such as the fireplaces of FIGS. 7-8 andFIGS. 12-15. FIGS. 1 and 2 illustrate an embodiment of a fireplace,fireplace insert, heat-generating unit, or heating device 10 configuredto operate with a source of combustible fuel. In various embodiments,the heating device 10 is configured to be installed within a suitablecavity, such as the firebox of a fireplace or a dedicated outer casing.The heating device 10 can extend through a wall 12, in some embodiments.

The heating device 10 includes a housing 20. The housing 20 can includemetal or some other suitable material for providing structure to theheating device 10 without melting or otherwise deforming in a heatedenvironment. The housing 20 can define a window 22. In some embodiments,the window 22 comprises a sheet of substantially clear material, such astempered glass, that is substantially impervious to heated air butsubstantially transmissive to radiant energy.

The heating device 10 can include a sealed chamber 14. The sealedchamber 14 can be sealed to the outside with the exception of the airintake 24 and the exhaust 26. Heated air does not flow from the sealedchamber to the surroundings; instead air, for example from in aninterior room, can enter an inlet vent 13 into the housing 20. The aircan pass through the housing in a conduit, or channel 15, passing overthe outside of the sealed chamber 14 and over the exhaust 26. Heat canbe transferred to the air which can then pass into the interior roomthrough outlet vent 16.

In some embodiments, the heating device 10 includes a grill, rack, orgrate 28, as in FIG. 2. The grate 28 can provide a surface against whichartificial logs may rest, and can resemble similar structures used inwood-burning fireplaces. In certain embodiments, the housing 20 definesone or more mounting flanges 30 used to secure the heating device 10 toa floor and/or one or more walls. The mounting flanges 30 can includeapertures 32 through which mounting hardware can be advanced.Accordingly, in some embodiments, the housing 20 can be installed in arelatively fixed fashion within a building or other structure.

As shown, the heating device 10 includes a fuel delivery system 40,which can have portions for accepting fuel from a fuel source, fordirecting flow of fuel within the heating device 10, and for combustingfuel. In the embodiment illustrated in FIG. 2, portions of an embodimentof the fuel delivery system 40 that would be obscured by the heatingdevice 10 are shown in phantom. Specifically, the illustrated heatingdevice 10 includes a floor 50 which forms the bottom of the sealedcombustion chamber 14 and the components shown in phantom are positionedbeneath the floor 50.

With reference to FIG. 2A, an example of a fuel delivery system isshown. The fuel delivery system 40 can include a regulator 120. Theregulator 120 can be configured to selectively receive a fluid fuel(e.g., propane or natural gas) from a source at a certain pressure. Incertain embodiments, the regulator 120 includes an input port 121 forreceiving the fuel. The regulator 120 can define an output port 123through which fuel exits the regulator 120. Accordingly, in manyembodiments, the regulator 120 is configured to operate in a state inwhich fuel is received via the input port 121 and delivered to theoutput port 123. In certain embodiments, the regulator 120 is configuredto regulate fuel entering the port 121 such that fuel exiting the outputport 123 is at a relatively steady pressure. The regulator 120 canfunction in ways similar to the pressure regulators disclosed in U.S.Pat. No. 7,434,447, filed on May 30, 2006, and U.S. patent applicationSer. No. 12/797,511, filed on Jun. 9, 2010, incorporated by referenceherein.

The output port 123 of the regulator 120 can be coupled with a sourceline or channel 125. The source line 125, and any other fluid linedescribed herein, can comprise piping, tubing, conduit, or any othersuitable structure adapted to direct or channel fuel along a flow path.In some embodiments, the source line 125 is coupled with the output port123 at one end and is coupled with a control valve 130 at another end.The source line 125 can thus provide fluid communication between theregulator 120 and the control valve 130.

The control valve 130 can be configured to regulate the amount of fueldelivered to portions of the fuel delivery system 40. Variousconfigurations of the control valve 130 are possible, including thoseknown in the art as well as those yet to be devised. In someembodiments, the control valve 130 includes a millivolt valve. Thecontrol valve 130 can comprise a first knob or dial 131 and a seconddial 132. In some embodiments, the first dial 131 can be rotated toadjust the amount of fuel delivered to a burner 135, and the second dial132 can be rotated to adjust a setting of a thermostat. In otherembodiments, the control valve 130 comprises a single dial 131.

In many embodiments, the control valve 130 is coupled with a burnertransport line or channel 137 and a pilot transport or delivery line141. The burner transport line 137 can be coupled with a nozzle assembly140 which can be further coupled with a burner delivery line 143. Thenozzle assembly 140 can be configured to direct fuel received from theburner transport line 132 to the burner delivery line or channel 143.

The pilot delivery line 141 is coupled with a safety pilot, pilotassembly, or pilot 180. Fuel delivered to the pilot 180 can be combustedto form a pilot flame, which can serve to ignite fuel delivered to theburner 135 and/or serve as a safety control feedback mechanism that cancause the control valve 130 to shut off delivery of fuel to the fueldelivery system 40. Additionally, in some embodiments, the pilot 180 isconfigured to provide power to the control valve 130. Accordingly, insome embodiments, the pilot 180 is coupled with the control valve 130 byone or more of a feedback line 182 and a power line 183.

The pilot 180 can comprise an igniter or an electrode configured toignite fuel delivered to the pilot 180 via the pilot delivery line 141.Accordingly, the pilot 180 can be coupled with an igniter line 184,which can be connected to an igniter actuator, button, or switch 186. Insome embodiments, the igniter switch 186 is mounted to the control valve130. In other embodiments, the igniter switch 186 is mounted to thehousing 20 of the heating device 10. The pilot 180 can also comprise athermocouple. Any of the lines 182, 183, 184 can comprise any suitablemedium for communicating an electrical quantity, such as a voltage or anelectrical current. For example, in some embodiments, one or more of thelines 182, 183, 184 comprise a metal wire.

The burner delivery line 143 is situated to receive fuel from the nozzleassembly 140, and can be connected to the burner 135. The burner 135 cancomprise any suitable burner, such as, for example, a ceramic tileburner or a blue flame burner, and is preferably configured tocontinuously combust fuel delivered via the burner delivery line 143.

The flow of fuel through the fuel delivery system 40, as shown, will nowbe described. A fuel is introduced into the fuel delivery system 40through the regulator 120 which then proceeds from the regulator 120through the source line or channel 125 to the control valve 130. Thecontrol valve 130 can permit a portion of the fuel to flow into theburner transport line or channel 132, and can permit another portion ofthe fuel to flow into the pilot transport line or channel 141. The fuelflow in the burner transport line 132 can proceed to the nozzle assembly140. The nozzle assembly 140 can direct fuel from the burner transportline or channel 132 into the burner delivery line or channel 143. Insome embodiments, fuel flows through the pilot delivery line or channel141 to the pilot 180, where it is combusted. In some embodiments, fuelflows through the burner delivery line or channel 143 to the burner 135,where it is combusted.

An air shutter 150 can also be along the burner delivery line 143. Theair shutter 150 can be used to introduce air into the flow of fuel priorto combustion at the burner 135. This can create a mixing chamber 157where air and fuel is mixed together prior to passing through the burnerdelivery line 143 to the burner 135. The amount of air that is needed tobe introduced can depend on the type of fuel used. For example, propanegas at typical pressures needs more air than natural gas to produce aflame of the same size.

The air shutter 150 can be adjusted by increasing or decreasing the sizeof a window 155. The window 155 can be configured to allow air to passinto and mix with fuel in the burner delivery line 143.

The air shutter 150, along with the burner 135 and the pilot 180 can bewithin the sealed combustion chamber 14. Because the combustion chamber14 is sealed, it can be difficult to access components within thecombustion chamber 14. For this reason some of the components are withinthe combustion chamber 14 but many are not. In some embodiments, onlythe components necessary for combustion are within the chamber 90 andall others are outside the chamber 14. For example, the other componentscan be in the channel 15 of the housing 20 (FIG. 1). It is necessary forconnecting pipes, lines or channels and some parts of other componentsto pass into the sealed combustion chamber 14 and remain partiallyinside the sealed combustion chamber 14 and partially outside. Fittingscan be used to allow the necessary components to pass into the chamber14 while otherwise sealing the entry point into the sealed combustionchamber 14.

As the air shutter 150 is within the sealed combustion chamber 14, itcan be difficult to adjust to the proper setting. In some currentlyavailable heaters, a long screw is used to adjust the air shutter. Thelong screw passes into the sealed combustion chamber through a fittingand the end attaches to the air shutter. Advancing or withdrawing thescrew into or out of the sealed combustion chamber can move the airshutter to adjust the size of the window. A long screw can be cumbersomeand does not provide any indication to the user as to the position ofthe air shutter.

FIGS. 3, 3A and 3B illustrate another embodiment of a heating device 10′and a fuel delivery system 40′ compatible with the heating device 10′.Numerical reference to components is the same as previously described,except that a prime symbol (′) has been added to the reference. Wheresuch references occur, it is to be understood that the components arethe same or substantially similar to previously-described components.

As can be seen in FIG. 3, a direct vent heating device 10′ can have ahousing 20′ which encloses a sealed chamber 14′ with a burner 135′inside the sealed chamber. FIG. 3A shows the heating device 10′ in apartially disassembled view. For example, part of the outer housing 20′,such as vents 13′, 16′ have been removed, as has the floor 50′. Thisview shows some of the components of the heating device 10′, such asparts of the fuel delivery system 40′.

Turning now to FIG. 3B an embodiment of a fuel delivery system 40′ isshown that can be compatible with many different heating devicesincluding the heating device shown in FIG. 3. The fuel delivery system40′ can include many of the components previously described with respectto FIG. 2A, such as a pilot assembly 180′, an igniter 186′ and a controlvalve 130′.

Also shown in FIG. 3B is a basket 52. The inner portion 54 of the basket52 can be part of the sealed chamber 14′. The basket 52 can be used tostore certain parts of the heating device such as components of the fueldelivery system 40′ within the sealed chamber 14′. The basket 52 canalso attach to the floor 50′ and can be configured to allow certaincomponents, pipes, wires, etc. to pass through the basket 52. Gaskets 56can be used to seal access points into the basket 52, floor 50′ or otherparts of the sealed chamber 14′.

FIGS. 4A-E illustrate one embodiment of an improved air shutter control60. In some embodiments, the air shutter control 60 can replace thenozzle assembly 140 in FIG. 2A, similar to the configuration shown inFIG. 3B. The burner transport line 137′ can connect to an inlet 62 onthe air shutter control 60. Fuel can be directed from the inlet 62through a valve 64 to an injector orifice or nozzle 66. The fuel can beinjected into the mixing chamber 157′ to mix with air introduced throughthe air shutter 150′ to pass into the burner delivery line 143′ to thenbe delivered to the burner 135′ for combustion.

Looking now at FIG. 5, as shown, an air shutter 150′ can comprise acylinder or other shape with a slot 80 sized to fit on ledge 68 of thevalve 64. The air shutter 150′ can be configured to move with the valve64. In some embodiments, the air shutter 150′ can be fastened on to thevalve 64 either at the ledge 68 or otherwise. This can be done, forexample, with a friction fit between the slot 80 and the ledge 68. Insome embodiments, the nozzle 66 can also be configured to move with thevalve. In some embodiments, the valve 64, the nozzle 66 and the airshutter 150′ all rotate about the same axis. In some embodiments, thenozzle 66 and the air shutter 150′ are coaxial.

The air shutter 150′ can also have a slot or hole 82. In someembodiments, the burner delivery line 143′ has a corresponding slot orhole 84. The overlap between the holes 82 and 84 can create a window155′ that can allow air to pass into the mixing chamber 157′ to mix withthe fuel.

The air shutter control 60 can have a user interface surface 70. Theuser interface surface 70 can be used to control the position of the airshutter 150′ and conversely the amount of air that can enter the mixingchamber 157′. The user interface surface 70 can comprise a knobconnected to the valve 64. In other embodiments, not shown, the userinterface surface 70 can comprise other types of mechanical controlssuch as a lever, a wheel, a switch, or some other device to transfer auser's movement to move the air shutter 150′. In other embodiments, alsonot shown, the user interface surface 70 can comprise an electrical orcomputer control, including but not limited to electrical buttons,electrical switches, a touch screen, etc.

According to some embodiments, the user interface surface 70 can beoutside of the sealed combustion chamber 14′ and the air shutter 150′can be inside of the sealed combustion chamber 14′. For example, theflange 76 can be used as a fitting to attach the air shutter control 60to a basket 52 or to a wall of or the floor 50′ of the sealed combustionchamber 14′. The injector orifice 66 and the part of the valve attachedto the air shutter can be inside the sealed combustion chamber 14′ whilethe rest of the valve, the flange 76 and the user interface surface 70can be outside of the sealed combustion chamber 14′.

FIG. 6 illustrates another embodiment of an air shutter 150′′′′.Numerical reference to components that are the same as previouslydescribed use the same number but include a quadruple prime symbol(′′′′). Where such references occur, it is to be understood that thecomponents are the same or substantially similar to previously-describedcomponents.

In FIG. 6, as in some embodiments described above, the air shutter canhave a body which defines a slot or hole 82′′′′ that overlaps with acorresponding slot or hole 84′′′′ in the burner delivery line, creatinga window 155′′′′ that can allow air to pass into the mixing chamber157′′′′ to mix with the fuel.

The air shutter can have a gear member 85 with a plurality of shutterteeth 87 on its outer surface. The air shutter can also have an airshutter control 60′′′′ with a user interface surface 70′′′′ that is ableto control the air shutter by means of a shaft 73 to which is secured tocontrol teeth 75 that cooperate with the shutter teeth 87. When a userrotates the user interface surface, the shaft 73 and control teeth 75rotate, the control teeth applying a force to the shutter teeth 87 whichrotates the shutter teeth, the body of the shutter and, thereby, theslot or hole 82′′′′, increasing or decreasing the size of the window. Insome embodiments the control teeth 75 are part of a collar 79 thatsurrounds the shaft 73. In other embodiments the control teeth are partof the shaft itself.

In various embodiments the shutter teeth 87 and control teeth 75 have avariety of designs. They can be cut, for example, as spur gears, bevelgears, helical gears, or any other tooth design known in the art.Additionally, various embodiments may have different tooth designs forthe shutter teeth 87 and the control teeth 75. For example, the controlteeth may be cut as a worm gear while the shutter teeth may be cut as aspur gear or a helical gear.

The gear ratio between the shutter teeth 87 and control teeth 75 canvary across different embodiments. In some embodiments where spur gearsare used, the ratio of shutter teeth to control teeth can be betweenabout 1.5 and about 2. In some embodiments it can be between about 2 andabout 3, between about 3 and about 5, between about 4 and about 7, orbetween about 5 and about 8. In some embodiments the ratio can begreater than 8. In some embodiments, the ratio can be between about 1.5and about 8, between about 2 and about 8, between about 3 and about 8,between about 4 and about 8, or between about 5 and about 8. In someembodiments, it can be between about 1.5 and about 16, between about 2and about 16, between about 4 and about 16, between about 6 and about16, or between about 8 and about 16.

Desirably, but not always, at least 120 degrees of rotation of the userinterface surface 70′′′′ (and/or shaft 73) is required to change the airshutter from a minimum airflow position with the window 155′′′′ fullyclosed or substantially fully closed, to a maximum airflow position withthe window 155′′′′ fully open or substantially fully open. In otherembodiments the gear ratio can be configured such that the userinterface surface 70′′′′ must rotate at least 150, 180, 210, 240, 270,300, 330, or 360 degrees in order to change the air shutter from aminimum airflow position to a maximum airflow position. This air shutteradjustment offers the user improved control over the airflow that mixeswith the fuel. In embodiments where even more precise control of theairflow is desired, the gear ratio can be set such that more than a 360degree rotation of the user interface surface 70′′′′ is required tochange the air shutter from a minimum airflow position to a maximumairflow position. In various embodiments at least 420, 480, 540, 600,660, or 720 degrees of rotation may be required.

In some embodiments, it can be preferable for the user interface 70′′′′and/or the shaft to rotate between about 120 and about 360 degrees tochange the air shutter from a minimum airflow position to a maximumairflow position. In some embodiments, the user interface and shaft mayrotate between about 120 and about 720 degrees, between about 180 andabout 720 degrees, between about 360 and about 720 degrees, or betweenabout 540 and 900 degrees to change the air shutter from a minimumairflow position to a maximum airflow position. In some embodiments, theuser interface and shaft may rotate between about 120 and about 180degrees, between about 180 and about 270 degrees, between about 270 andabout 360 degrees, between about 360 and about 450 degrees, betweenabout 450 and about 540 degrees, between about 540 degrees and about 630degrees, or between about 630 and about 720 degrees to change the airshutter from a minimum airflow position to a maximum airflow position.

In some embodiments the size of the window 155′′′′ formed between theair shutter slot or hole 82′′′′ and the burner delivery line slot orhole 84′′′′ can be adjusted. With reference to FIG. 6, the size of thewindow can be defined in terms of an angle θ formed by two linesemanating from the center of a cross-section of the shutter and in thesame plane as the cross-section, where one line passes through a firstedge of the window 155′′′′ when fully open, and where the second linepasses through a second edge of the window 155′′′′ when fully open. Forexample, a window 155′′′′ that occupies a third of the circumference ofthe shutter when the window is fully open would have an angle θ of 120degrees. Various embodiments of the air shutter can have a window thatis at least 5, 10, 20, 30, 40, 45, 50, 60, 70, 80, 90, 100, 110, 120,130, 140, 150, 160, 170, or 180 degrees. Various embodiments of the airshutter can have a window that is less than 5, 10, 20, 30, 40, 45, 50,60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, or 180 degrees.Varying the rotation required to change the air shutter from a minimumairflow position to a maximum airflow position can be done by adjustingthe gear ratio, as described above, by adjusting the size of the window,or by adjusting both the gear ratio and the size of the window.

Additionally, some embodiments can have two separate air shuttercontrols, an air shutter control with a gear ratio set for coarsecontrol of the air shutter and an air shutter control with a gear ratioset for fine control of the air shutter. The air shutter control set forcoarse control can interlock with the shutter teeth at one side of thegear member, and the air shutter control set for fine control caninterlock with the shutter teeth at another side of the gear member.Both of the air shutter controls can have different gear ratios withrespect to the shutter teeth, such that the coarse air shutter controlrequires less angular motion than the fine air shutter control to makethe same adjustment to the air shutter. Alternatively, an air shuttercan have two gear members, one of which interfaces with a coarse airshutter control and another of which interfaces with a fine air shuttercontrol.

The shaft position relative to the axis of rotation of the shutterdepends on the design of the shutter teeth 87 and the control teeth 75.In some embodiments the shaft 73 is substantially perpendicular to theaxis of rotation of the shutter 150′′′′, as illustrated by FIG. 6. Whilenot a necessary part of the invention, a shaft substantiallyperpendicular to the axis of rotation of the shutter 150′′′′ offers someadvantages. For example, it will typically allow the air shutter control60′′′′ to be on the same side of the gas fireplace assembly as the dialsfor the control valve, in contrast to the positioning seen in FIG. 3B.Having the air shutter control and the dials for the control valve neareach other can simplify operation of the gas fireplace assembly.

As discussed with respect to various embodiments above, the air shuttercontrol 60′′′′ can have a user interface surface 70′′′′ that cancomprise a knob, other types of mechanical controls, or an electrical orcomputer control. In embodiments of FIG. 6 with an electrical orcomputer control, a stepper motor can be used to rotate the shaft 73,allowing for precision control of the air shutter 150′′′′. The airshutter control can also be designed to provide some indication of theposition of the air shutter.

Additional details of the air shutter 150′′′′ and the air shuttercontrol are disclosed in U.S. patent application Ser. No. 12/797,446,which is hereby incorporated by reference in its entirety.

Direct Vent Fireplace with Cooling Structure

The embodiments described in FIGS. 1-5 disclose a gas fireplace assemblywith several control system embodiments to control the performanceparameters of the gas fireplace. Although the description of theembodiments of FIGS. 7 and 8 provided below do not include specificdetails of a control system, it is understood that the following directvent fireplace with cooling structure embodiments can include any of theabove described control systems, in whole or in part, and anycombination thereof of the various components or features of the controlsystems described above.

In the illustrated embodiments of FIGS. 7 and 8, another embodiment of adirect vent gas fireplace assembly, or heating device 10″, is shown.Numerical reference to components is the same as previously described,except that a double prime symbol (″) has been added to the reference.Where such references occur, it is to be understood that the componentsare the same or substantially similar to previously-describedcomponents.

FIG. 7 shows a perspective view of the heating device 10″ in anassembled view, with the exception of the front grill of the inlet vent13″ having been removed for clarity. The control system and fueldelivery system details are not shown; however, the control system andfuel delivery system can be any of the embodiments or a combinationthereof, as described in detail above. FIG. 8 shows the heating device10″ in a partially disassembled view. For example, part of the controlsystem and fuel delivery system has been removed for clarity.

The heating device 10″ can include a housing 20″ that encloses a sealedcombustion chamber 14″ with a burner 135″ inside the sealed combustionchamber. The sealed chamber 14″ can be sealed to the outside with theexception of the air intake 24″ and the exhaust 26″. Heated air does notflow from the sealed chamber 14″ to the surroundings; instead air, forexample from in an interior room, can enter an inlet vent 13″ into thehousing 20″. The heating device 10″ can further include an aircirculation system 80 having one or more of a heating channel 15″, inletvent 13″, climate control outlet vent or exhaust 16″, cooling fan 82,cooling channel 84, and climate control fan 86.

As shown, the air circulation system 80 can be configured to deliverheated air to the interior room, or interior space, where the heatingdevice 10″ is installed, and to deliver cooling air to a front face 17of the heating device 10″.

The heating channel, conduit, or passage 15″ can be disposed about, andextend proximate, the external surface of the sealed combustion chamber14″. The channel 15″ can include a spaced gap between the sealedcombustion chamber 14″ and the fireplace housing 20″. The channel 15″can be located on one or more sides of the fireplace assembly. Forexample, as shown, the channel 15″ can be located on the bottom side,the back side, and the top side of the fireplace assembly. In someembodiments, the channel 15″ can be located on the right side and/orleft side of the fireplace assembly. The fluid channel 15″ can besufficiently proximate to the combustion chamber to heat the fluid, orroom air, which is delivered through the channel 15″. In someembodiments, the channels can share a wall with the housing defining thecombustion chamber 14″.

With continued reference to FIGS. 7 and 8, the channel 15″ can beconfigured to receive interior room air, or climate control air, fromthe climate control air inlet vent 13″, deliver the climate control airabout a proximity of the sealed combustion chamber 14″, and expel heatedclimate control air out of the climate control outlet vent 16″. Heatemitted by the combustion of fuel and combustion air can be transferredto the climate control air delivered through channel 15″ and generatethe heated air.

The term “climate control” as used herein, is a broad term used in itsordinary sense, and includes features directed to the distribution ofwarmed fluid, such as, for example, interior room air, outside ambientair, or the like, and any combination thereof, to influence or controlthe room temperature where the fireplace is installed. For example,climate control air is distinguished from combustion air; however, insome embodiments, climate control air can provide the source ofcombustion air to the chamber 14″, and/or the combustion air source canprovide at least a portion of the climate control air.

The climate control fan 86 is configured to deliver, or blow, airthrough the channel 15″. The climate control fan 86 can be locatedadjacent the channel 15″, or generally positioned anywhere in fluidcommunication to the channel 15″ flow path. The climate control fan 86can have a variety of typical fan features, e.g. directed flow vents,variable speed controls, or the like. The climate control fan 86 can bea transflow, or centrifugal, configuration fan. In some embodiments, theclimate control fan 86 can be an array of one or more axial propellerfans. In some embodiments, the air flows through the channel 15″ bynatural convection, without the assistance of a fan.

The air circulation system 80 can include a second channel, or thecooling channel 84. The cooling channel 84 can be configured to deliveroutput air from the cooling fan 82 to front face 17, i.e. the exteriorsurface of the window 22″. In the illustrated embodiment in FIG. 8, thecooling channel 84 extends under the floor 50″ of the sealed combustionchamber in a forward direction toward the front face 17, and thenextends upward on a lower portion of the front face 17.

The cooling channel 84 can include a cooling exhaust vent 88 located atthe downstream end of the cooling channel. The cooling exhaust vent 88can be positioned proximate or adjacent to, the window 22″ and frontface 17. The air can cool the exterior surface of the window 22″ to asurface temperature that can be safe to the touch. The cooling channel84 can deliver a portion of air received by the channel 15″ through theinlet vent 13″. In some embodiments, the cooling channel can beconfigured to receive air directly from any air source, e.g. theinterior room, outside ambient air, or the like. In addition, thecooling channel 84 and cooling fan 82 can deliver air from a dedicatedinlet vent.

As shown, the cooling exhaust vent 88 generally extends, or spans,substantially the full width of the fireplace assembly's front face 17.In some embodiments, the cooling exhaust vent 88 can span a portion ofthe front face, e.g. ¼, ½, ¾, substantially the entire width, or thelike, across the front face 17. The vent 88 can be configured to directair evenly across and over the window 22″ exterior surface via aconstant geometry exit area across the vent 88 width. In someembodiments, the cooling exhaust vent 88 can be configured to directincreased proportions of the cooling air flow mass to specific portionsof the window. For example, increased cooling air flow can be directedto localized hot spots that have relatively higher surface temperatures,or to portions of the window 22 most likely to incur user contact, suchas adjacent a control knob or a door or window handle.

In addition, though FIG. 8 shows the cooling exhaust vent 88 only on thebottom of the window, it is to be understood that the cooling exhaustvent 88 can be located at many different locations along the front face17. For example, the cooling exhaust vent 88 can be located along one ormore of the sides, the top, and/or the bottom of the front face 17. Inaddition, the cooling exhaust vent 88 can include one or more coolingfans 82 and can comprise one or more cooling channels 84 which may ormay not be connected.

FIGS. 9-11 illustrate one embodiment of the cooling structure where itcomprises multiple cooling channels. In the illustrated embodiment, thecooling structure comprises three connected cooling channels: a bottomchannel 61, a left side channel 63, and a right side channel 65. InFIGS. 10 and 11, the arrows represent the path of airflow through thecooling structure.

In some embodiments, the rear side 53 of the cooling structure can havea window mounted to it, and the air that exits the cooling structurewill directly cool the exterior surface of the window, as describedabove. In other embodiments, the cooling structure can have windowsmounted to the rear side 53 and the front side 51 such that the air thatexits the cooling structure will enter the space between the windows tothereby cool the front window.

As illustrated in FIG. 10, some air that exits the bottom channel canexit directly toward the front face, helping cool it, while some airthat exits the bottom channel can flow into other channels. In someembodiments, as described above, all of the air that exits the bottomchannel can go to immediately cool the front face. In other embodiments,all of the air that exits the bottom channel can enter other channels.

Air can exit the channels to cool the front face through a variety ofmeans. In some channels, the air can exit through one or more largeroutlets 81. In other channels, the air can exit through a plurality ofsmaller outlets 83 that can be round, ovular, or any other shape. Stillother channels such as the bottom channel illustrated in FIGS. 9-11 canbe configured such that air exits through multiple types of openings,such as larger 81 or smaller outlets 83. Additionally or alternatively,channels can be configured such that air exiting the channel to cool thefront face can exit at varying angles relative to the length of thechannel. For example, the bottom channel illustrated in FIGS. 9-11 isconfigured such that air exiting through the smaller outlets 83 exits ata different angle than air exiting through the larger outlets 81.

It is understood that any type or combination of openings that allow airto exit the channels to cool the front face can be used. Similarly, anyexit angle or combination of exit angles can be used in the coolingstructure. Different sizing and positioning of openings can focusairflow on desired areas, such as areas with relatively high surfacetemperatures or areas more likely to incur user contact, as discussedabove. Additional channels can provide additional locations to positionopenings. For example, in some embodiments, the cooling structure can bethe same as the embodiment illustrated by FIGS. 9-11, but with openingsin the top channel sized and spaced substantially similar to those usedin the side channels 63, 65.

Returning to FIG. 8, the cooling fan 82 is configured to blow airthrough the cooling channel 84. In embodiments where there are multiplecooling channels 84, as illustrated in FIGS. 9-11, the cooling fan 82can blow air into one or more of the cooling channels. The followingdisclosure regarding the cooling fan 82 is understood to apply equallyto embodiments with multiple cooling channels as it does to embodimentswith a single cooling channel. Descriptions of the cooling channel 84refer to one, some, or all of the cooling channels.

The cooling fan 82 can be located adjacent the cooling channel 84 andthe channel 15″, or generally positioned anywhere in fluid communicationto the cooling channel 84 and the channel 15″ flow path. As mentionedpreviously, the cooling channel 84 and cooling fan 82 can deliver airfrom a dedicated inlet vent which may or may not be connected to thechannel 15″. The cooling fan 82 can have a variety of typical fanfeatures, e.g. directed flow vents, variable speed controls, or thelike. The cooling fan 82 can be a transflow, or centrifugal,configuration fan. In some embodiments, the cooling fan 82 can be anarray of one or more axial propeller fans.

The cooling fan 82 can generally span a sufficient width of the coolingchannel 84 to provide a consistent and even flow of cooling air across asubstantial portion of the window 22″. In some embodiments, the coolingfan 82 can span ¼, ½, ¾, the entire width, or any other sufficientportion of the cooling channel 84 width, or the window 22″ width, thatis sufficient to deliver cooling air over the window 22″. The coolingfan 82 can be sized to provide sufficient capacity, or air mass flowrate capability, to cool the exterior surface of the window 22″ to safetemperatures. The cooling airflow exiting the vent 88 can generally flowup substantially the full height off the window 22″. In someembodiments, the cooling air can flow over a portion of the window 22″height, e.g. ¼, ½, ¾, substantially the entire height, or the like, upthe window 22″. The cooling fan 82 can be positioned under the sealedcombustion chamber 14″ and generally upstream of the climate control fan86; thus, the cooling fan can be located between the inlet vent 13″ andthe climate control fan 86. In some embodiments, the climate control fan86 can be located upstream of the cooling fan 82.

The cooling fan 82 can generally be positioned in a first half of thechannel 15″ extending from the air inlet vent 13″. As described above,the channel 15″ can define a flow path from the front face 17 under thefloor 50″, up the back side of the chamber 14″, and over the top side ofthe chamber 14″ to the outlet vent 16″. In some embodiments, the coolingfan 82 can be positioned in a first ¼, ⅓, ⅔, or any portion thereof, ofthe channel 15″ flow path. Similarly, the cooling fan 82 can bepositioned in any portion of the channel 15″ such that the air drawninto and blown out of the fan 82 is not substantially heated by thecombustion in the sealed combustion chamber 14″. In some embodiments,heated air can be drawn into the cooling fan 82 and directed to thewindow 22″. In some embodiments, the cooling fan 82 can be locatedoutside of the channel 15″.

The cooling fan 82 can include a control module, which is not shown,that is coupled to, and can control, the operation of the fan 82 and theburner 135″. The control module can cool the window 22″ by activatingthe fan 82 when the burner 135″ is in operation, or activated. Thecontrol module can further deactivate, or turn off, the burner 135″ whenthe control module receives input, or a lack thereof, that the coolingfan 82 is not functioning properly. In this manner, the burner 135″turns off and prevents the window 22″ from becoming excessively hot.

In some embodiments, the control module controls the cooling fan 82 toremain on and blowing cooling air to the window 22″ after the burner135″ is deactivated. In some embodiments, the cooling fan 82 iscontrolled to remain on for a predetermined amount of time after theburner 135″ is turned off. The cooling fan can remain on for two, five,ten, or any number of minutes to maintain a cool window temperature. Theextended cooling fan operation prevents excessive window temperaturesthat can result from the transfer of residual heat in the walls, orstructure, of the sealed combustion chamber, or firebox. Thepredetermined time can be factory set, or can be adjusted by the userduring or after installation. In some embodiments, the predeterminedtime can be adjusted via a control module interface, which is not shown.

In some embodiments, the fireplace assembly can include a thermocoupleproximate the window 22″, or more preferably an exterior surface ofwindow 22″. The thermocouple can provide a feedback control system withthe control module that can keep the cooling fan 82 activated until thewindow achieves a predetermined safe temperature. The predeterminedtemperature can be factory set or selected by the user afterinstallation.

The direct vent heating device 10″ can provide efficient heating anddoes not require a chimney for safe operation. The direct vent heatingdevice 10″ can direct outside ambient air through a combustion ventsystem 90 for heat generating combustion, and thus does not depriveinterior living spaces of oxygen or heated air.

The heating device 10″ can include a combustion vent system 90, or flue,that can extend outward from the heating device 10″ and be directedhorizontally through an external wall or vertically to a roof. As shown,the vent system 90 includes two collinear ducts, the inner and outerflue, or the combustion air intake duct 24″ and the combustion airexhaust duct 26″. The illustrated air exhaust 26″ is smaller in diameterthan air intake 24″, and air exhaust 26″ extends within the larger airintake 24″ and generally shares a common longitudinal axis. The internalair exhaust 26″ generally directs combustion exhaust gas out of thefireplace. The external air intake 24″ generally draws external, oroutside, air into the fireplace through the annular space between thesmaller diameter combustion exhaust 26″ and the larger diameter airintake 24″. External air is generally the ambient air outside of thebuilding structure being heated. In some embodiments, the air intake 24″can be the smaller diameter and extend within the larger diameter airexhaust 26″. The collinear vent system can improve the system efficiencyof heating device 10″ because the air entering in the annular space iswarmed by passing over and about the heated combustion exhaust 26″ priorto combustion at the burner 135″.

Dual Direct Vent and Vent Free Fireplace

The embodiments described in FIGS. 1-8 disclose a gas fireplace assemblywith several control system embodiments to control the performanceparameters of the gas fireplace and a cooling structure for a face ofthe fireplace. Although the description of the embodiments of FIGS.12-15 provided below does not include specific details of a controlsystem, it is understood that the following duel direct vent andvent-free fireplace embodiments can include any of the above describedcontrol systems, in whole or in part, and any combination of the variouscomponents or features of the control systems described above.

In the illustrated embodiments of FIGS. 12-15, another embodiment of aheating device 10′′′, a dual-function direct vent and vent free gasfireplace assembly, is shown. The heating device 10′′′ is able tofunction in either a direct vent configuration or a vent freeconfiguration. A direct vent fireplace, as described above, can bevented out through the wall or through the roof to the exterior of astructure, building, or home. A vent free gas fireplace does not requirean external vent or a chimney, rather the exhaust is vented directlyinto the interior of a structure, building, or home. The heating device10′′′ can include many similar characteristics and/or features as theheating device 10″ of FIGS. 7 and 8. Numerical reference to componentsis the same as previously described, except that a triple prime symbol(′′′) has been added to the reference. Where such references occur, itis to be understood that the components are the same or substantiallysimilar to previously-described components.

With reference to FIG. 12, the dual-function direct vent and vent freegas fireplace 10′′′ is shown in an assembled view. The control systemand fuel delivery system details are not shown; however, the controlsystem and fuel delivery system can be any of the embodiments or acombination thereof, as described in detail above or as furtherdescribed below. FIG. 13 shows the heating device 10′′′ in a partiallydisassembled cross-section view. For example, parts of the controlsystem and the fuel delivery system have been removed for clarity.

With reference to FIGS. 12 and 13, the heating device 10′′′ desirablycan function as both a direct vent fireplace system or as a vent freefireplace system. The dual system fireplace desirably can providesuitable heat in a variety of scenarios, improving the operability ofthe fireplace in general, e.g. operable both with and without a sourceof electricity. The fireplace 10′′′ can advantageously include at leasttwo features that can accommodate the interchangeable direct vent andvent free configurations within the single fireplace. These features caninclude a closing mechanism for a combustion chamber exhaust outlet 95and a removably installed sealed door 92 and/or window 22′′′.

The fireplace 10′ can include an exhaust pipe 26′′′ that can maintainfluid communication between the sealed combustion chamber 14′′′ and theambient environment for expelling the combustion exhaust from the burner135′′′ disposed in the sealed combustion chamber. As has been explainedherein, the exhaust pipe 26′′′ is used in the direct vent configuration.The combustion chamber outlet 95 at the exhaust pipe 26′′′ can includean exhaust cover, or baffle 96, that can be positioned over thecombustion chamber exhaust outlet 95 to seal the combustion chamber14′′′ from the ambient environment. This can allow the heating device10′′′ to be used in the vent free configuration.

The exhaust cover 96 can fit over the exhaust outlet 95 and preventheated air from exiting the chamber 14′′′ and colder external ambientair from entering the chamber. The cover 96 can have a sealing member,or gasket, non-metallic interface, or the like, to facilitate thesealing feature of the cover. The sealing member can be capable ofexposure to the high temperatures of the chamber 14′′′.

It should be noted that the exhaust cover 96 as shown, does not coverthe air intake 24′. In some embodiments, the fireplace 10′′′ cancontinue to draw, via a pressure differential between the air intake andthe combustion at the burner, or the like, external ambient air tocombust at the burner 135′′′. In some embodiments, the air intake 24′can similarly be closed when using the heating device 10′′′ in the ventfree configuration. As will be described in more detail below, for ventfree operation the window 22′′′ can be opened or removed to allow forproper exhaust and/or air inflow. As will be understood, opening orremoving the door 92 and/or window 22′′′ unseals the previously sealedcombustion chamber 14′′′ and allows for the exchange of air and exhaustbetween the combustion chamber and its surroundings.

With particular reference to FIG. 13, the cover 96 can be pivotablycoupled to a controller, or arm member 98, that desirably canselectively open or close the exhaust outlet 95. The controller 98 canposition the cover 96 over the exhaust pipe 26′′′ to completely closethe exhaust, or can position the cover adjacent the exhaust 26′′′ tocompletely open the exhaust. In addition, the controller 98 can positionthe cover 96 anywhere between these two positions. Alternatively thecover could have a number or fixed positions or only partially coverand/or uncover the exhaust pipe 26′′′. The controller 98 can be any formof motion inducing device, e.g. mechanically via a cam, an arm, or thelike, or electronically, pneumatically, magnetically, or the like.

The controller 98 can be coupled to the cover 96 and removably coupled,e.g. magnetically, spring-loaded, interference fit, or the like, to thewindow 22′′′ at a window coupling 97. The controller 98 can release fromthe window coupling 97 when the window is opened or removed from a faceof the fireplace. The cover 96 and/or controller 98 can be biased suchthat the cover 96 moves to the closed position when the controller 98 isreleased from the window coupling 97. The cover 96 and/or controller 98can be biased by a spring, or the like, to pivotably or laterally moveinto position over the exhaust outlet 95. Thus, the exhaust outlet 95can be automatically closed, or substantially sealed, upon opening orremoval of the window 22′′′. This can facilitate moving the heatingdevice to the vent free fireplace configuration.

In some embodiments, the cover 96 can be positioned by other automated,or automatic, means upon opening or removal of the window and/or door,which are known to those of ordinary skill in the art. In someembodiments, the controller 98 can be a spring loaded member in acompressed configuration with the window installed, thereby urging thecover 96 away from the exhaust; however, removal of the windowuncompresses the spring and urges the cover 96 toward the exhaust 26′.In some embodiments, the controller 98 can be one or more arm memberscoupled to an interior surface of the combustion chamber, e.g.

top, front, back, right side, left side, or the bottom of the combustionchamber. In some embodiments, the controller 98 can be a solenoidpowered to prevent spring-biased movement of the cover 96 over theexhaust 26′′′, and upon loss of electricity the solenoid allows thespring-biased cover 96 to seal off the exhaust pipe 26′ from thechamber.

The fireplace 10′′′ can be modified from the direct vent configurationto the vent free configuration manually or automatically. In someembodiments, the exhaust cover can be moved to the closed position toclose and seal the chamber exhaust, via any of the various meansdescribed above as well as similar or equivalent means not described. Inthe event of a loss of electricity, proper functioning of the fireplaceelectronic components may be prevented. For example, electronicallycontrolled fuel valves, regulators, and/or circulation fans may notwork. To maintain continued heat generation to a building interior, thedirect vent fireplace 10′′′ can be readily and safely converted to avent free fireplace 10′′′ by closing the cover 96 and opening the sealedface of the chamber 14′′′.

The fireplace 10′′′ can include a door 92 disposed on the front face ofthe fireplace, coupled, in one embodiment, by at least one hinge 91. Thedoor 92 can include a frame disposed about a window 22′′′. The frame canbe any suitable material, e.g. metallic, or the like. The window 22′′′can provide a clear visual of the flame, logs, or the like, disposedwithin the chamber and configured to provide a natural flame appearance.The door 92 can lockingly seal and engage the chamber 14′′′. The doorcan include a handle 94 that can control a locking, or latchingmechanism, and provide a feature to securely and safely hold onto, orgrab, the door 92 to open, close, or generally control the door.

The window 22′′′ and/or door 92 can establish a sealed side face of thesealed combustion chamber 14′′′ when the fireplace 10′′′ is configuredto operate as a direct vent heating device. In particular, the window22′′′ can establish the front side face of the fireplace. In someembodiments, the side of the fireplace 10′′′ can be any face, orsurface, of the fireplace that extends from the bottom to the top of thefireplace, or an intermediate portion thereof. In some embodiments, thewindow 22′′′ can be removable to provide an open front face of thefireplace 10′′′ and provide the heat transfer from the fireplace throughthe open face to the building interior, rather than, or in combinationwith, fan-driven forced ventilation. In some embodiments, the window22′′′ can be positioned on any face of the fireplace 10′′′, e.g. front,back, right, left, top, or bottom.

The window 22′′′ can be a variety of different configurations, e.g.single piece, multi-piece, framed, with or without handles, or the like.The window 22′′′ can be fabricated and have material characteristicssimilar to the windows 22, 22′, 22″ described above. In someembodiments, only a portion of the window 22′′′ can be removed fromsealed engagement with the fireplace front side face, or any facethereof. In some embodiments, the entire window 22′′′ or a portion ofthe window 22″ can be completely removed from the face of the heatingdevice, such that the window is either installed on the fireplace or notinstalled on the fireplace. In some embodiments, the window 22′′′ can beremoved from the door 92. In some embodiments, the window, or portionthereof, is hingedly, such as by hinges 91, or the like, coupled to thefireplace 10′′′, and can be rotated or pivoted about the coupling todisengage the sealed interface between the window and the fireplace10′′′ front face 17′. The window can be pivotably controlled by arotatable handle, much like a typical casement window device. The windowcan be slidably movable to open all or a portion of the fireplace face.In some embodiments, a multi-piece window can be rotated and folded awayfrom the front face of the fireplace.

Though a window 22′′′ is described above, it should be understood that awindow is not required and that the window can be replaced with otherstructures, including heat radiating structures. Also, any part of theheating device 10′′′ can be opened or removed to move the heating device10′′′ to the vent free configuration, so long as by so doing thecombustion chamber is no longer sealed allowing the free exchange of airand exhaust between the combustion chamber and the interior roomenvironment, or the environment where the heating device is located. Forexample, the heating device 10′′′ can be a cast iron stove/fireplace orhave the appearance of a cast iron stove/fireplace. In such anembodiment, it is unlikely that there will be a window, but a door maybe located at the front face, or on another surface that can serve thesame or similar purposes as the window described herein.

In some embodiments, opening the window or door can expose an inlet ventthat was previously blocked to allow air to enter through the newlyexposed and opened inlet.

In some embodiments, the fuel delivery system can include electroniccontrollers and/or electronic mechanisms, e.g. electronic regulator,valves, air shutter, or the like (not shown). The fuel delivery systemcomponents can be similar to the fuel delivery system 40 describedabove, or the systems and devices disclosed in the incorporated U.S.Pat. No. 7,434,447 and U.S. patent application Ser. No. 12/797,511. Uponloss of electricity, the electronic regulator, and/or fuel valve, can beconfigured to automatically shut down, or deactivate, to preventaccumulation of uncombusted fuel within the combustion chamber 14′′′should the flame at the burner 135′′′ extinguish. In some embodiments,the electric valve assembly controlling direct vent combustion canbecome inoperable when electric power is lost to the fireplace 10′′′. Insome embodiments, a loss of electricity to the fireplace 10′′′ canrender the unit useless as a heat source.

In some embodiments, the fuel delivery system can advantageously includea both a manual and an automatic control valve, where the control valveis used to control the amount of fuel flowing to the burner. The manualvalve can be configured to provide less fuel to the burner and therebyprovide a lower energy output as compared to the automatic controlvalve. The manual valve can be operated manually by a control knob onthe fireplace 10′′′. The reduced energy, e.g. decreased BTU/hr output ofthe flame, or the like, can eliminate or reduce the volume of combustionair emissions emitted into the building interior and maintain safe airquality conditions, even with the combustion chamber exhaust outlet 95covered, or closed, by the exhaust cover 96. In some embodiments, theburner and/or flame characteristics can be controlled by the first knob131′′′ and/or the second knob 132′′′.

In some embodiments, the coupling 97 can be part of a circuit, such thatopening the window also opens the circuit. The circuit can be connectedto the electronic powered automatic control valve which powers down whenthe circuit is opened. Fuel flow can then be directed to the manualvalve operating at a lower BTU/hr rating. Alternatively, a button switchmay be depressed or released when the window is opened or removed,thereby deactivating the automatic control valve.

In some embodiments, the fuel delivery system can advantageously includea second valve and/or other fuel system components (not shown), that canbe manually opened, controlled, and ignited. The second valve can,either alone, or in combination with a second burner (not shown),provide a lower energy output. In some embodiments, the valve can beoperated manually by a control knob 99 disposed on an outer surface ofthe fireplace 10′′′. The reduced energy, e.g. decreased BTU/hr output ofthe flame, or the like, can eliminate or reduce the volume of combustionair emissions emitted into the building interior and maintain safe airquality conditions, even with the combustion chamber exhaust outlet 95covered, or closed, by the exhaust cover 96. In some embodiments, theburner and/or flame characteristics can be controlled by the first knob131′′′ and/or the second knob 132′′′.

With reference to FIG. 12, the dual-function direct vent and vent freefireplace 10′′′ can further include one or more oxygen depletion sensors(ODS) 106. The ODS can include the various features and characteristicsdisclosed in U.S. Pat. No. 7,434,447 and U.S. patent application Ser.No. 12/797,511, incorporated by reference as described above. The ODScan include a pilot and a thermocouple arranged such that the flame fromthe pilot heats the thermocouple and the heat indicates oxygen levels,for example reduced oxygen levels can result in an extinguished pilotflame and decreased thermocouple temperatures. The oxygen depletionsensor can indicate when oxygen levels reach dangerous low levels. Insome embodiments, the ODS can always be operational, for example, whenthe fireplace 10′′′ is operating in the direct vent mode and externalambient air provides the combustion air to the burner. In someembodiments, the ODS can become operational upon opening or removal ofthe window 22′′′ and the closure of the exhaust 26′′′. The ODS can beparticularly suitable for operation in embodiments whereby the externalambient air intake is closed in the vent free configuration.

In some embodiments, the fireplace 10′′′ can include multi-fuelcapability, allowing the fireplace to operate on one fuel among a groupof multiple types of fuel, e.g. natural gas, propane, or the like. Sucha dual fuel configuration, described above, and further described inincorporated U.S. Pat. No. 7,434,447 and U.S. patent application Ser.No. 12/797,511, can provide a regulator configured to function withindistinct pressure ranges, ranges that are typical of the proposed gases,or fuels, for the fireplace operation.

Turning now to FIGS. 14 and 15, the flow circulation path within thefireplace 10′′′ is shown for an embodiment of a direct ventconfiguration. The fireplace 10′′′ is shown with two circulation fans, afirst fan 100 for a combustion vent system 90′ and a second fan 86′ fora heating air circulation system 80′. Together the two flow systems 80′and 90′ can provide complete, or substantially complete, combustion andconsistent heat transfer to the room interior where the fireplace 10′′′is installed and functioning in a direct vent configuration.

The circulation flow path of the combustion vent system 90′ is shown bythe arrows depicted in FIG. 14. The combustion vent system 90′ caninclude a combustion air intake 24′′′, an exhaust 26′′′, a combustionair channel 25, a baffle 102, and a combustion fan 100. The combustionsystem 90′ can be configured similar to the systems and embodimentsdescribed above, bringing external ambient air from the air intake24′′′, into the combustion chamber 14′′′ and then expelling the exhaustair out the exhaust 26′′′ to the external ambient environment. Thus, theinterior air generally does not take part in the combustion process andcan generally avoid being either the combustion air or mingling with theexhaust emission from the fireplace.

The combustion air intake and exhaust are desirably collinear asdescribed above with respect to heating device 10′′′. The combustion airchannel 25 can be a spaced gap between two panels of the chamber 14′′′,such as between an interior panel 34 and an exterior panel 36 thatestablish the outside boundary, or surfaces, of the sealed combustionchamber 14′′′. The channel 25 desirably extends along a top portion ofthe chamber 14′′′, then down a rear portion of the chamber to the baseof a floor. The channel 25 desirably exits to the burner 135′′′ at thebottom of the combustion chamber 14′′′, where the combustion air drawninto the chamber via the combustion fan 100 desirably is directed to theburner and to the window 22′′′. The interior panel, or conduit panel 36,desirably can be parallel to the rear firebox panel 34 within the sealedcombustion chamber 14′′′.

The combustion fan desirably can be disposed within the combustionchamber 14′′′ to direct the incoming ambient combustion air toward theburner 135′′′ and the window 22′′′. In some embodiments, the baffle 102can be disposed adjacent the floor and can direct the combustion airtoward the window 22′′′ and/or the burner 135′′′. The use of combustionfan 100 to force combustion air toward the burner can increase, orimprove, the mixing of fuel and combustion air thereby improvingcombustion characteristics at the burner flame. For example, improvedcombustion can result in cleaner combustion of the fuel and reduced airpollutants in the combustion emissions of the fireplace 10′′′.

The combustion fan 100 can generally be positioned in any suitablearrangement within the chamber 14′′′. In some embodiments, thecombustion fan 100 can be positioned in a first ¼, ⅓, ⅔, the final ¼, ⅓,or any portion thereof, of the heating channel 25 flow path, oraccordingly, of the floor portion of the heating channel 15′′′.Similarly, the combustion fan 100 can be positioned in any portion ofthe channel 15′′′, e.g. a first ¼, ⅓, ⅔, the final ¼, ⅓, or any portionthereof, such that the air drawn into and blown out of the fan 100 isnot substantially over-heated by the combustion in the sealed combustionchamber 14′′′. In some embodiments, the combustion fan 100 can belocated outside of the channel 15′′′.

In some embodiments, ambient air can be drawn into the combustion fan100 and directed to the window 22′′′. As shown, the baffle 102 is angledwith respect to the window 22 such that air directed at the baffle 102will flow upwards towards the burner 135′′′ or towards the window 22′′′.As can also be seen, a small gap is formed between the burner 135′′′ andthe baffle 102. This small gap can direct air flow to the window 22′′′.This air flow directed at the window can include ambient air at a lowertemperature than the exhaust air. As will be understood, the lowerportion of the window may be in close contact with the flames and heatfrom combustion at the burner 135′′′. Directing a flow of air at thelower portion of the window can help cool the window 22′′′.

The combustion airflow pushed by the combustion fan 100 can generallyflow up substantially the full height off the window 22′′′ on thechamber inside surface. In some embodiments, the combustion air can flowover a portion of the window 22′′′ height, e.g. ¼, ½, ¾, substantiallythe entire height, or the like, up the window 22′′′. In otherembodiments, the combustion air can flow over a portion of the window22′′′ after first flowing through cooling channels as described withreference to FIGS. 9-11. The combustion fan 100 can be positioned withinthe sealed combustion chamber 14″ and generally upstream of the baffle102; thus, the combustion fan 100 can be located between the air intake24′′′ and the window 22′′′.

The circulation flow path of the fluid circulation system 90′ is shownby the arrows depicted in FIG. 15. The fluid circulation system 90′ caninclude a vent inlet 13′′′, a heating channel 15′′′, a climate controloutlet vent or exhaust 16′′′, and climate control fan 86′. The fluidcirculation system 80′ brings interior air into a flow path disposedabout the combustion chamber 14′′′. Though the vent inlet 13′′′ is shownon the top of the fireplace 10′′′, the vent inlet can function in asimilar manner as those discussed previously, including vent inlet 13shown in FIG. 1 to draw into the fireplace 10′′′ to be heated within thefireplace.

Advantageously, the interior air can cool the rear firebox panel 34surfaces of the fireplace 10′′′ chamber, and cool the glass window 22′′′while at the same time absorbing heat energy and heating the air flowwithin the channel 15′′′, and then dispersing the heated air out of thefireplace to heat the room interior.

As can be seen, the window 22′′′ can be a dual paned window having afirst pane 93 and a second pane 95. The second pane 95 can form part ofthe sealed chamber and can be closest to the burner 135′′′. The channel15′′′ can run between the two panes of window 22′′′, cooling the windowand decreasing the burn risk and fire risk. Even when the fan 86′ is noton or running, the dual paned window creates an added barrier betweenthe glass closest to the flames and the room interior. This barrier canalso be effective to reduce the burn and fire risks.

The heating channel 15′′′ can extend from the air vent inlet 13′′′disposed about the flue, or the combustion air intake 24′′′ at a topportion of the heating device 10′′′, rearward between the top portion ofthe fireplace and the top portion of the chamber 14′′′. The channel15′′′ then progresses downward and behind the rear firebox panel 34 ofthe chamber 14′′′ to the volume underneath the floor. The channel 15′′′then proceeds from under the floor through the space gap between the twopanes 93, 95 of the dual paned window 22′′′ on the door 92. The heatingchannel 15′′′ can vary according to suitable geometry, and can take anyform set forth above. It can also comprise multiple cooling channelsalong the front face, as described with reference to FIGS. 9-11. Theinterior air exchanges heat from the chamber 14′′′ generallycontinuously as the air travels through the at least three portions(rear, bottom, front) of the channel 15′′′. In particular, the heatingair forced through by the climate control fan 86′ can cool the frontface window 22′′′ to prevent the surface from becoming excessively hotduring use of the fireplace 10′′′.

The climate control fan 86′ can be disposed in the heating channel15′′′. The fan 86′ draws interior air into the fireplace through the airvent inlet 13′′′. The fan 86′ can have the various characteristicsdescribed above with respect to cooling fan 82 and/or climate controlfan 86.

The climate control fan 86′ can generally be positioned in a first half,or a first two-thirds, of the channel 15′′′ extending from the air inletvent 13′′′. As described above, the channel 15′′′ can define a flow pathfrom the top surface of the fireplace 10′′′, down the back side of thechamber 14′′′, and under the floor of the combustion chamber 14′′′ tothe window 22′′′ between the first pane 93 and the second pane 95, thenout the outlet vent 16′′′.

In some embodiments, the climate control fan 86′ can be positioned in afirst ¼, ⅓, ⅔, or any portion thereof, of the channel 15′′′ flow path.Similarly, the climate control fan 86′ can be positioned in any portionof the channel 15′ such that the air drawn into and blown out of the fan86′ is not substantially over-heated by the combustion in the sealedcombustion chamber 14′′′. In some embodiments, heated air can be drawninto the climate control fan 86′ and directed to the window 22′′′. Insome embodiments, the climate control fan 86′ can be located outside ofthe channel 15′′′.

Although this invention has been disclosed in the context of certainpreferred embodiments and examples, it will be understood by thoseskilled in the art that the present invention extends beyond thespecifically disclosed embodiments to other alternative embodimentsand/or uses of the invention and obvious modifications and equivalentsthereof. In addition, while a number of variations of the invention havebeen shown and described in detail, other modifications, which arewithin the scope of this invention, will be readily apparent to those ofskill in the art based upon this disclosure. It is also contemplatedthat various combinations or subcombinations of the specific featuresand aspects of the embodiments may be made and still fall within thescope of the invention. Accordingly, it should be understood thatvarious features and aspects of the disclosed embodiments can becombined with or substituted for one another in order to form varyingmodes of the disclosed invention. Thus, it is intended that the scope ofthe present invention herein disclosed should not be limited by theparticular disclosed embodiments described above, but should bedetermined only by a fair reading of the claims that follow.

Similarly, this method of disclosure, is not to be interpreted asreflecting an intention that any claim require more features than areexpressly recited in that claim. Rather, as the following claimsreflect, inventive aspects lie in a combination of fewer than allfeatures of any single foregoing disclosed embodiment. Thus, the claimsfollowing the Detailed Description are hereby expressly incorporatedinto this Detailed Description, with each claim standing on its own as aseparate embodiment.

What is claimed is:
 1. A heating apparatus comprising: a sealedcombustion chamber; a burner within the sealed combustion chamber; afuel channel for directing a fuel from a fuel source external the sealedcombustion chamber to the burner; an air shutter within the sealedcombustion chamber, said air shutter comprising a rotatable sleeve, therotatable sleeve configured to rotate about a shutter axis and adjustthe size of a shutter opening; an air shutter control comprising ashaft, the air shutter control cooperating with the air shutter suchthat rotating the shaft rotates the rotatable sleeve; and wherein theshaft must rotate at least 180 degrees to change the air shutter from aminimum airflow position to a maximum airflow position.